Calorimeter

Abstract

A calorimeter for the measurement of a quantity of heat given up by a fluidic medium in at least one heat exchanger, with an impellerless flow velocity measuring device as well as temperature sensors for determining the forward flow-return flow temperature difference, including a multiplier for forming the product from the flow velocity and the forward flow-return flow temperature difference; and also a quantizer for the formation of a pulse train having a frequency which is proportional to the product, as well as a cumulative counting device for the pulses of the pulse train connected to the output thereof. The flow velocity measuring device is activated only at predetermined points in time or moments, whereby the frequency of these measuring moments is determined approximately proportional to an auxiliary variable which represents a measure for the importance of a possible change in a parameter determining the heating quantities on the measured result, and in which a second multiplier is connected ahead of the quantizer which the output signal of the first multiplier is multiplied with a value proportional to the timewise interval between two measurement switching moments.

What is claimed is: 
     
       1. In a calorimeter for the measurement of the heat quantity given up by a fluidic medium in at least one heat exchanger, including an acoustic flow velocity measuring device, and temperature sensors for the determination of the forward-return flow temperature difference, a multiplier for the formation of the product of the flow velocity and the forward-return flow temperature difference, a quantizer for forming a pulse train at a frequency proportional to the product, and a cumulating counting device connected to the output of the quantizer for the pulses of the pulse train; the improvement comprising in that the flow velocity measuring device is activated only at predetermined measuring moments wherein the frequency of these measuring moments is generally proportional to an auxiliary variable representative of a measure for the significance of a possible change of at least one parameter determining the heat output on the measured result, said parameter being chosen from the group consisting of a generally heat output-proportional signal and a signal proportional to the time-wise gradient of the forward flow temperature, and a second multiplier connected to the input of the quantizer in which the output signal of the first multiplier is multiplied with a value proportional to the timewise spacing between two measuring moments. 
     
     
       2. Calorimeter as claimed in claim 1, said auxiliary variable comprising a generally heat outputproportional signal. 
     
     
       3. Calorimeter as claimed in claim 2, comprising a summing arrangement for the output signals of the temperature sensors associated with the heat forward flow and heat return flow, the output signal of said summing device forming the auxiliary variable. 
     
     
       4. Calorimeter as claimed in claim 3, comprising a further quantizer receiving the output signal of the summing device forming a pulse train with a frequency proportional to the magnitude at the output signal of the summing device and being connected with the second input of the second multiplier, wherein the first input of the second multiplier is connected with the output of the first multiplier, the pulse train being conducted to a trigger input of the flow velocity measuring device. 
     
     
       5. Calorimeter as claimed in claim 3, an operational element being directly connected to the output of the summing device so as to form a juncture, said operational element having one input for receiving the output signal of the summing device and a second input for receiving the output signal of a random generator, said random generator including an upwardly bounded data storage. 
     
     
       6. Calorimeter as claimed in claim 5, said operational element comprising a third multiplier. 
     
     
       7. Calorimeter as claimed in claim 5, said operational element comprising a further summing device. 
     
     
       8. Calorimeter as claimed in claim 5, said random generator comprising a noise generator. 
     
     
       9. Calorimeter as claimed in claim 4, each said quantizer comprising an integrator and a threshold stage connected to the output thereof, the output of which forms the output of the first quantizer and wherein the output signal of the threshold stage provides for resetting of the integrator.